Sudden Alignment Difficulty

I’m fairly new to lasers and light burn so take that into account. I recently picked up a Creality Falcon 2 Pro 40w, spent a few hours getting it assembled and set, and was off to learning to use it and Lightburn without any concerns at all. Fast forward a few days and I notice it’s X and Y are off when doing some key tags towards the bottom half of the work area. I redid the calibration and alignment procedures several times and each time it does the same thing. I burn the alignment images freshly each time I redo the process and then set the offset so that’s it’s accurate and it continues to lose its X,Y in a progressive manner from the center outwards.

The image provided was taken at the lower right of the workspace, as you can see the XY begin to shift the further it gets from the center mark and correct offset. If I reburn this grid on the left, top, or bottom, the alignment offset corresponds to that direction, IE the upper left will have the XY offset up and to the left. I’ve gone so far as to take the entire enclosure apart and rebuild it, checked all screws and belts, there’s no play on the camera location as it’s firmly mounted to a stationary part of the sliding lid. It just started to do this suddenly after several days of use and I can’t seem to figure it out for the life of me, any ideas?

Question. When you are doing the calibration are you setting the thickness of the material and the pattern on top?

Given Creality is quite short in terms of focal range - therefore a wider lens - the corners will become natural areas of smaller accuracy. Especially if you change the focal length by using a thicker material vs. calibration

Although less ideal, as a rule of thumb and if you need hyper accuracy, make sure to use the center 60% of your bed and avoid the corners

I appreciate the quick reply!

I did the calibrations at the center of the bed each time and made sure to set the thickness. Here’s an image of a burn I just did as an example. The X to the left is over the center of the bed, the one to the right has an offset to it, even with just the few inches shift to the right. Unfortunately it’s not just at the extremes of the workspace.

question: when doing the camera calibration what type of lens are you selecting?

Normal or fisheye?

Standard, however I did try both along the way just to make sure I wasn’t making a mistake.